This invention relates generally to trucks and, more specifically, to trucks useful on skateboards or roller skates.
Trucks are important elements in the design of modern skateboards and roller skates (collectively xe2x80x9cskatesxe2x80x9d). Trucks not only support the wheels of the skateboard or roller skates, they provide the user with a significant degree of directional control.
In a typical skate truck, directional control is accomplished by providing the truck with two primary components, a truck hanger and a mounting bracket. The truck hanger has opposed axle elements for carrying a pair of opposed skate wheels and is attached to the mounting bracket using a pair of in-line mounting pins, a hanger pivot and a king pin. The hanger pivot protrudes upwardly from the truck hanger and the king pin protrudes downwardly from the mounting bracket. The two primary elements of the truck are assembled with the hanger pivot disposed within a pivot bore defined within the mounting bracket, and with the king pin disposed within a hanger flange attached to the truck hanger. The hanger pivot is not rigidly retained within the pivot bore, so that the hanger pivot has some degree of play within the hanger bore. The hanger flange is retained on the king pin by a king pin nut. The hanger flange is retained on the king pin between a pair of elastomeric cushion elements. By this assembly, the hanger flange retains some side-to-side play when the user of the skateboard or roller skate leans to one side or the other. Such side-to-side play tends to cause the wheels to turn slightly to one side or the other. Thus, the user can control the forward direction of the skate by shifting his or her body from one side of the skate to the other.
Unfortunately, there is a problem with such trucks of the prior art. The elastomeric cushion elements which sandwich the hanger flange to the king pin tend to wear out quickly. Also, excessive side-to-side stress on the truck can dislocate or even damage the cushion elements.
Accordingly, there is a need for a simple and inexpensive skateboard/roller skate truck which avoids these problems with the prior art.
The invention satisfies this need. The invention comprises a truck hanger having opposed axle elements, a wheel mounted on each axle element, a hanger flange and a hanger pivot, and a mounting bracket for attachment of the truck hanger to a skateboard or roller skate. The mounting bracket comprises a base plate, a pivot bore, a king pin protruding downwardly from the mounting bracket, an inner cushion element disposed around the proximal end of the king pin and an outer cushion element disposed around the distal end of the king pin. The truck hanger is affixed to the mounting bracket with the hanger pivot disposed within the pivot bore and with the hanger flange disposed over the king pin between the inner cushion element and the outer cushion element. In the invention, both the inner cushion element and the outer cushion element comprise an elastomeric outer portion and a substantially rigid liner portion bonded to the elastomeric portion.
The rigid liner portion of both cushion elements preferably has a tubular moiety and a flange moiety. The liners impart to the cushion element increased rigidity and stability.